This workbook is designed primarily for graduate library school students in a supervised laboratory setting as an adjunct to a formal course on computer based reference services. The DIALOG system has the capability to search several large on line files, and the workbook is designed to be used in conjunction with the Lockheed DIALOG Manual. Eight of the ten exercises cover basic instruction and drill of DIALOG commands and features, and the remaining two provide summary reviews and drills. Though not intended for self-instruction, the exercises may be done either individually or in group mode. Appendices include suffix, prefix, language and publication type codes, and LIMIT commands. (WBC)